Almost every weekend, Yuta Aoki heads to Tokyo's Shibuya Ward armed with a camera, a stabilizer and a microphone. His mission is to find and speak to Japanese people, but they must look happy or, at least, not busy — "I don't want any trouble," he says with a laugh. He's hunting for opinions: "Is 'gaijin' an offensive term?" "What do you think of tattoos?" On a good day, 1 in every 10 people will stop to chat.